ETC1 standing for Ericsson Texture Compression, version 1, is a texture compression scheme which is implemented in many devices such as mobile phone and touchpad devices. It has been optimized initially for efficient hardware-implementation, in particular for texture data decompression.
But there is a need for these devices to be also able to handle texture data which is compressed using DXT1, standing for DirectX Texture Compression, codec 1. To this end, DTX1-compressed texture data which is received is to be converted into ETC1 format, before being decompressed according to this latter compression format. But such conversion must be rapid enough for not slowing down the image display rate significantly.
One object of the present invention is therefore to provide rapid conversion for texture data, from a first compression format to a second one.
In particular, the invention aims at converting texture data from first to second compression format while minimizing handling of color values which are encoded with full color bit-length.